The Oudeh Oilfield is located at the northeast of Syria. The upper Cretaceous Shiranish reservoir in this oilfield is mainly comprised of porous grainstone/packstone in a carbonate ramp. Under a tectonic setting of being high northwestwards and low southeastwards, the oilfield is cut into several fault blocks by approximately N-S trending and E-W trending faults,among which several major N-S trending ones are growth faults,which are also the dominant faults in this oilfield. Height difference of paleotopography caused by contemporaneous faulting has control over sedimentation and diagenesis in some extent therefore it controls the formation and distribution of excellent reservoir. Coarse-grained grainstone/packstone and favorable zone of digenesis, such as meteoric water leaching and dolomitization, mainly distribute ina banded zone that is close to one side of growth faults,which results in nearly S-N directional zonal distribution of the reservoir. Based on the above-mentioned study,a genesis model of Shiranish reservoir is established and illustrated. This model provides good reference and guidance for prediction of excellent reservoirs and exploration of similar reservoirs.